Hello,
HMS Gurkha sighted a U-boat on the surface by moonlight (U-53) at 2327/23 February in 60°32' N, 06°14' W. Depth-charging began at 2358/23 with three runs. ASDIC contact had faded before a fourth run was carried out so there is little doubt that the sinking occurred in the early hours of 24th February unless someone can come up with evidence the U-boat survived to be lost through another cause.
Best regards,
Platon